Light emitting device, backlight module and liquid crystal display device

Abstract

This application discloses a light-emitting device, belonging to the field of display technology. The light-emitting device includes: a circuit board, multiple light-emitting units, and multiple adhesive blocks. The circuit board includes multiple first pads and multiple second pads, which are alternately arranged in a first direction, with gaps separating adjacent first and second pads. The multiple light-emitting units are electrically connected to adjacent first and second pads, respectively. In a second direction, multiple adhesive blocks are arranged on the same side of the multiple light-emitting units, and the adhesive blocks and the multiple light-emitting units are alternately arranged in the first direction, with the second direction intersecting the first direction. The orthographic projection of the adhesive blocks on the circuit board is located outside the area containing the gaps; or, the extension length of the portion of the gap covered by the adhesive block is less than the dimension of the adhesive block in the first direction and less than the dimension of the adhesive block in the second direction. This application can improve the bonding effect of the adhesive blocks.

Description

Light emitting device, backlight module and liquid crystal display device TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a light emitting device, a backlight module and a liquid crystal display device. BACKGROUND

[0002] Liquid crystal display devices have a wide range of application scenarios in life, such as electronic devices such as mobile phones and tablet computers. The liquid crystal display device usually includes a backlight module and a liquid crystal display panel, and the light emitting device is an important component of the backlight module.

[0003] In the related art, the light emitting device includes a circuit board, a plurality of light emitting units and a plurality of adhesive blocks. The circuit board includes a plurality of first pads and a plurality of second pads arranged alternately in a first direction, and the first pad and the second pad distributed adjacent to each other have a partition gap therebetween. The plurality of light emitting units are located on the circuit board, and the light emitting units are electrically connected to the adjacent first pad and second pad respectively. The plurality of adhesive blocks are located on the circuit board, and the plurality of adhesive blocks are arranged alternately with the plurality of light emitting units in the first direction, and the second direction is perpendicular to the first direction. The orthogonal projection of the adhesive block on the circuit board partially overlaps with the region where the partition gap is located.

[0004] However, the surface of the circuit board for setting the light emitting unit will form a recess at the partition gap, so if the adhesive block is arranged above the partition gap and the overlapping area of the adhesive block and the partition gap is large, the adhesion effect between the light guide plate and the light emitting device will be poor.

[0005] SUMMARY

[0006] Embodiments of the present application provide a light emitting device, a backlight module and a liquid crystal display device. The technical solution is as follows:

[0007] In one aspect, a light emitting device is provided, which includes a circuit board, a plurality of light emitting units and a plurality of adhesive blocks. The circuit board includes a plurality of first pads and a plurality of second pads, the plurality of first pads and the plurality of second pads are arranged alternately in a first direction, and the first pad and the second pad distributed adjacent to each other have a partition gap therebetween. The plurality of light emitting units are located on the circuit board, and the light emitting units are electrically connected to the adjacent first pad and second pad respectively. The plurality of adhesive blocks are located on the circuit board, and the plurality of adhesive blocks are arranged on the same side of the plurality of light emitting units in a second direction, and the second direction intersects the first direction. The orthogonal projection of the adhesive block on the circuit board is located outside the region where the partition gap is located, or the extension length of the portion of the partition gap covered by the adhesive block is less than the size of the adhesive block in the first direction and less than the size of the adhesive block in the second direction.

[0008] Optionally, a projection of the first pad on a plane where the circuit board is located is larger than an area of a projection of the second pad on the plane where the circuit board is located; wherein a projection of the adhesive block on the circuit board is located in an area where the first pad is located; or an area of a part of the projection of the adhesive block on the circuit board that is located in the area where the first pad is located is larger than an area of a part of the projection of the adhesive block on the circuit board that is located in the area where the second pad is located.

[0009] Optionally, the partition gap comprises: a first sub-partition gap, a second sub-partition gap and a third sub-partition gap connected in sequence; the first sub-partition gap and the third sub-partition gap both extend in a direction parallel to the second direction, and the second sub-partition gap extends in a direction parallel to the first direction; wherein, in the second direction, the third sub-partition gap is closer to the light-emitting unit than the first sub-partition gap.

[0010] Optionally, in the case that the projection of the adhesive block on the circuit board overlaps with the area where the partition gap is located, there is a part of the first sub-partition gap that is covered by the adhesive block, and there is no part of the second sub-partition gap and the third sub-partition gap that is covered by the adhesive block.

[0011] Optionally, the second pad comprises: a first conductive part, a conductive transition part and a second conductive part connected in sequence in the second direction; a size of the first conductive part in the first direction is smaller than a size of the second conductive part in the first direction; a size of the conductive transition part in the first direction gradually increases in a direction from the first conductive part to the second conductive part; wherein at least one of the conductive transition part and the second conductive part is used to electrically connect with a conductive circuit in the circuit board.

[0012] Optionally, the first sub-partition gap comprises: a first sub-gap, a connecting sub-gap and a second sub-gap connected in sequence; the first sub-gap is located between the first conductive part and the first pad, the connecting sub-gap is located between the conductive transition part and the first pad, and the second sub-gap is located between the second conductive part and the first pad; wherein a width of the first sub-gap is equal to a width of the connecting sub-gap and equal to the second sub-gap.

[0013] Optionally, the plurality of second pads are divided into a plurality of pad groups, one pad group comprises at least two second pads arranged continuously in the first direction, and the two second pads distributed at the outermost sides in one pad group are respectively a first second pad and a last second pad.

[0014] In one of the pad groups, the size of the first conductive part in the second direction of each of the second pads gradually decreases from the first second pad to the last second pad, and the size of the second conductive part in the second direction of each of the second pads gradually increases from the first second pad to the last second pad.

[0015] Optionally, in one of the pad groups, the size of the conductive transition part in the second direction of each of the second pads is equal.

[0016] Optionally, the width of the partition gap is 0.1-0.3 mm.

[0017] Optionally, the extension direction of the partition gap intersects the first direction and the second direction; the included angle between the extension direction of the partition gap and the first direction ranges from 30 to 60 degrees.

[0018] Optionally, the circuit board has oppositely arranged first and second sides, and the light emitting units are distributed on the circuit board at positions close to the first side; wherein in the second direction, the size of the adhesive block is smaller than the minimum distance between the light emitting units and the second side.

[0019] Optionally, the adhesive block comprises a first adhesive part and a second adhesive part connected to each other, the first adhesive part is closer to the first side relative to the second adhesive part, and in the first direction, the size of the first adhesive part is smaller than the size of the second adhesive part.

[0020] Optionally, in the case that the orthographic projection of the adhesive block on the circuit board overlaps the region where the partition gap is located, the orthographic projection of the second adhesive part on the circuit board overlaps the region where the partition gap is located, and the orthographic projection of the first adhesive part on the circuit board does not overlap the region where the partition gap is located.

[0021] Optionally, the orthographic projection of the first adhesive part on the circuit board is rectangular, and the orthographic projection of the second adhesive part on the circuit board is trapezoidal.

[0022] Optionally, the second adhesive part has two sharp corners distributed in the first direction, and the tips of the two sharp corners are arc-shaped.

[0023] Optionally, in the case that the orthographic projection of the adhesive block on the circuit board overlaps the region where the partition gap is located, the orthographic projection of one of the sharp corners in the second adhesive part on the circuit board overlaps the region where the partition gap is located.

[0024] Optionally, the circuit board comprises: a second protective layer, a second connecting layer, a second trace layer, a substrate layer, a first trace layer, a first connecting layer and a first protective layer which are sequentially stacked; the first trace layer is located between the substrate layer and the plurality of light emitting units, the plurality of first pads and the plurality of second pads are located on the first trace layer; the sum of the thicknesses of the substrate layer and the first trace layer is greater than the sum of the thicknesses of the first connecting layer and the first protective layer; the sum of the thicknesses of the substrate layer and the second trace layer is greater than the sum of the thicknesses of the second connecting layer and the first protective layer.

[0025] Optionally, the light emitting device further comprises a release film, the release film is located on the side of the plurality of adhesive blocks away from the plurality of first pads and the plurality of second pads; the release film comprises a main body and a plurality of extending portions connected to the main body, the plurality of extending portions are located on the side of the main body close to the plurality of light emitting units, and in the first direction, the plurality of light emitting units and the plurality of extending portions are arranged alternately, and the extending portions are located between two adjacent light emitting units.

[0026] In another aspect, a backlight module is provided, comprising: a light guide plate and any one of the light emitting devices described above, the light emitting surface of the light emitting device faces the side surface of the light guide plate, and the circuit board in the light emitting device is adhered to the back surface of the light guide plate through the plurality of adhesive blocks.

[0027] In yet another aspect, a liquid crystal display device is provided, characterized in that the display device comprises: the backlight module described above, and a liquid crystal display panel located on the light emitting side of the backlight module.

[0028] The technical scheme provided by the embodiments of the present application has at least the following beneficial effects: by letting the orthographic projection of the adhesive block on the circuit board be located outside the region of the partition gap between the adjacent first pad and second pad, or by letting the extension length of the part of the partition gap between the adjacent first pad and second pad covered by the adhesive block be less than the size of the adhesive block in the first direction and less than the size of the adhesive block in the second direction, the area of the overlap between the partition gap and the adhesive block can be ensured to be as small as possible or not to overlap, so as to avoid the adhesive block being arranged above the partition gap as much as possible, so as to improve the adhesion effect of the adhesive block. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical schemes in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0030] FIG. 1 is a schematic diagram of a planar structure of a light emitting device in the related art;

[0031] FIG. 2 is a schematic diagram of a planar structure of a light emitting device according to an embodiment of the present application;

[0032] FIG. 3 is a schematic diagram of a cross-sectional structure of a light emitting device according to an embodiment of the present application;

[0033] FIG. 4 is a schematic diagram of a planar structure of another light emitting device according to an embodiment of the present application;

[0034] FIG. 5 is a schematic diagram of a planar structure of another light emitting device according to an embodiment of the present application;

[0035] FIG. 6 is a partial enlarged view of a first pad and a second pad according to an embodiment of the present application;

[0036] FIG. 7 is a schematic diagram of a distribution of a plurality of first pads and a plurality of second pads according to an embodiment of the present application;

[0037] FIG. 8 is a schematic diagram of a light path of light emitted by a light emitting unit according to an embodiment of the present application;

[0038] FIG. 9 is a top view of an adhesive block according to an embodiment of the present application;

[0039] FIG. 10 is a schematic diagram of a light path of light emitted by another light emitting unit according to an embodiment of the present application;

[0040] FIG. 11 is a schematic diagram of a planar structure of another light emitting device according to an embodiment of the present application;

[0041] FIG. 12 is a schematic diagram of a cross-sectional structure of a circuit board according to an embodiment of the present application;

[0042] FIG. 13 is a schematic diagram of a planar structure of another light emitting device according to an embodiment of the present application;

[0043] FIG. 14 is a schematic diagram of a planar structure of another light emitting device according to an embodiment of the present application;

[0044] FIG. 15 is a flowchart of a manufacturing method of a light emitting device according to an embodiment of the present application;

[0045] FIG. 16 is a schematic diagram of a cross-sectional structure of a backlight module according to an embodiment of the present application;

[0046] FIG. 17 is a schematic diagram of a planar structure of a backlight module according to an embodiment of the present application. DETAILED DESCRIPTION

[0047] To make the objectives, technical solutions and advantages of the present application clearer, the following will further describe the embodiments of the present application in detail with reference to the accompanying drawings.

[0048] FIG. 1 is a schematic diagram of a planar structure of a light emitting device in the related art. As shown in FIG. 1, the light emitting device includes a circuit board 1', a plurality of light emitting units 2', and a plurality of adhesive blocks 3'. The circuit board 1' includes a plurality of first pads 11' and a plurality of second pads 12' arranged alternately in a first direction x', and the first pad 11' and the second pad 12' adjacent to each other have a partition gap 10' therebetween. The plurality of light emitting units 2' are located on the circuit board 1', and the light emitting unit 2' is electrically connected to the first pad 11' and the second pad 12' adjacent thereto, respectively. The plurality of adhesive blocks 3' are located on the circuit board 1', and the plurality of adhesive blocks 3' are arranged alternately with the plurality of light emitting units 2' in the first direction x', and a second direction y' is perpendicular to the first direction x'. The orthogonal projection of the adhesive block 3' on the circuit board 1' partially overlaps with the region where the partition gap 10' is located.

[0049] As shown in FIG. 1, in the related art, the partition gap 10' is generally a straight line segment and extends in a direction parallel to the second direction y'. The region where the partition gap 10' is located passes through the orthogonal projection of the adhesive block 3' on the circuit board 1', so that the area of the adhesive block 3' overlapping with the corresponding partition gap 10' is large.

[0050] However, the surface of the circuit board 1' for arranging the light emitting unit 2' is recessed at the partition gap 10', so that if the adhesive block 3' is arranged above the partition gap 10' and the area of the adhesive block 3' overlapping with the partition gap 10' is large, the proportion of the area of the adhesive block 3' overlapping with the partition gap 10' in the adhesive block 3' is large, and the adhesion effect between the light guide plate and the light emitting device is poor.

[0051] It should be noted that the light emitting device shown in FIG. 1 is only a schematic diagram of a partial structure of the light emitting device, and the part of the light emitting device shown in FIG. 1 includes three light emitting units 2' arranged in sequence from left to right. Moreover, in order to clearly show the projection relationship between the first pad 11', the second pad 12', and the light emitting unit 2', the leftmost light emitting unit is not shown, and only the remaining two light emitting units 2' are shown, and the light emitting unit 2' is not pattern filled. In addition, in order to clearly show the projection relationship between the adhesive block 3', the first pad 11', and the second pad 12', the adhesive block 3' is not pattern filled.

[0052] Therefore, an embodiment of the present application provides a light emitting device to improve the foregoing problems.

[0053] Fig. 2 is a schematic diagram of a planar structure of a light emitting device according to an embodiment of the present application, and Fig. 3 is a schematic diagram of a cross-sectional structure of a light emitting device according to an embodiment of the present application. As shown in Figs. 2 and 3, the light emitting device includes a circuit board 1, a plurality of light emitting units 2, and a plurality of adhesive blocks 3. The adhesive blocks 3 can be used to fix the light emitting device to a light guide plate, thereby forming a backlight module.

[0054] Exemplarily, the circuit board 1 is a flexible circuit board.

[0055] The circuit board 1 includes a plurality of first pads 1201 and a plurality of second pads 1202, and the plurality of first pads 1201 and the plurality of second pads 1202 are alternately arranged in a first direction x. The first pads 1201 and the second pads 1202 arranged adjacently have a partition gap 12a therebetween. Here, the plurality of first pads 1201 and the plurality of second pads 1202 are alternately arranged one by one, that is, one second pad 1202 is arranged between two adjacent first pads 1201, and one first pad 1201 is arranged between two adjacent second pads 1202.

[0056] Exemplarily, the first pads 1201 and the second pads 1202 are made of metal materials.

[0057] The plurality of light emitting units 2 are arranged on the circuit board 1, and the light emitting units 2 are electrically connected to the adjacent first pads 1201 and second pads 1202, respectively. The first pad 1201 and the second pad 1202 electrically connected to the same light emitting unit 2 are connected to the positive electrode and the negative electrode of the light emitting unit 2, respectively, or are connected to the negative electrode and the positive electrode of the light emitting unit 2, respectively.

[0058] Exemplarily, the partition gap 12a in the embodiment of the present application refers to the partition gap 12a between the first pad 1201 connected to one of the two adjacent light emitting units 2 and the second pad 1202 connected to the other light emitting unit 2. There is also a gap for partitioning between the first pad 1201 and the second pad 1202 electrically connected to the same light emitting unit 2, which can be referred to as an auxiliary partition gap 12b.

[0059] In one implementation, the extension directions of the partition gap 12a and the auxiliary partition gap 12b can be straight lines, and the extension direction of the partition gap 12a can be parallel to the extension direction of the auxiliary partition gap 12b. In another implementation, the extension direction of the partition gap 12a can be a broken line, and the extension direction of the auxiliary partition gap 12b can be a straight line.

[0060] It should be noted that, since the partition gap 12a is mainly optimized in the embodiments of the present application, the gap between the adjacent first pad 1201 and the second pad 1202 in the embodiments of the present application refers to the partition gap 12a.

[0061] The plurality of adhesive blocks 3 are arranged on the circuit board 1, and the plurality of adhesive blocks 3 are arranged on the same side of the plurality of light emitting units 2 in the second direction y, and the second direction y intersects the first direction x. For example, the second direction y can be perpendicular to the first direction x, and the first direction y and the first direction x can both be parallel to the plane on which the circuit board 1 is located. Here, the plurality of adhesive blocks 3 and the plurality of light emitting units 2 are alternately arranged in the first direction x. In a possible implementation, one adhesive block 3 is arranged between two adjacent light emitting units 2, and one light emitting unit 2 is arranged between two adjacent adhesive blocks 3. In another possible implementation, two or more adhesive blocks 3 are arranged between two adjacent light emitting units 2. The embodiments of the present application do not limit this.

[0062] The plurality of adhesive blocks 3 are arranged on the same side of the plurality of light emitting units 2 in the second direction y, so that the plurality of adhesive blocks 3 can reliably fix the light emitting device and the light guide plate (for example, the light guide plate 5 shown by the dashed line in FIG. 3), and the light emitting surface of the light emitting unit 2 faces the side surface of the light guide plate, that is, the light emitting device provided by the embodiments of the present application can be applied to a side-in backlight module.

[0063] The plurality of adhesive blocks 3 and the plurality of light emitting units 2 are alternately arranged in the first direction x, so that in the second direction y, as far as possible, no adhesive block is arranged on the light emitting surface of the light emitting unit 2, thereby avoiding affecting the light path of the light emitted by the light emitting unit 2, so as to avoid the problem of uneven light emission of the backlight module.

[0064] It should be noted that, in order to clearly show the positional relationship between the light guide plate and the light emitting device when the light emitting device provided by the embodiments of the present application is applied to the backlight module in FIG. 3, the position of the light guide plate 5 is also shown by a dashed line in FIG. 3.

[0065] In a possible embodiment, as shown in FIG. 2, the orthographic projection of the adhesive block 3 on the circuit board 1 is located outside the region where the partition gap 12a is located. That is, the orthographic projection of the adhesive block 3 on the circuit board 1 does not coincide with the region where the partition gap 12a is located.

[0066] In another possible embodiment, as shown in FIG. 4, which is a schematic diagram of a planar structure of another light emitting device provided in the embodiments of the present application, the orthogonal projection of the adhesive block 3 on the circuit board 1 overlaps the area where the partition gap 12a is located, and the extension length of the portion of the partition gap 12a covered by the adhesive block 3 is smaller than the size of the adhesive block 3 in the first direction x and smaller than the size of the adhesive block 3 in the second direction y. That is, the area where the orthogonal projection of the adhesive block 3 on the circuit board 1 overlaps the area where the partition gap 12a is located is small.

[0067] Since the surface of the circuit board 1 on which the light emitting unit 2 is arranged (hereinafter referred to as the first surface) is recessed at the partition gap 12a, the distance between the recessed portion of the first surface and the light guide plate is larger in the third direction z, and the distance between the solder pad of the first surface and the light guide plate is smaller in the third direction z in the backlight module including the light emitting device provided in the embodiments of the present application, as shown in FIG. 3. The third direction z is perpendicular to the first direction x and perpendicular to the second direction y.

[0068] Suppose that the adhesive block 3 includes a first portion of the adhesive block located above the recessed portion of the first surface, and a second portion of the adhesive block located above the solder pad (the first solder pad 1201 or the second solder pad 1202) of the first surface. Since the degree to which the two sides of the second portion of the adhesive block are pressed by the circuit board 1 and the light guide plate 5 is larger than the degree to which the two sides of the first portion of the adhesive block are pressed by the circuit board 1 and the light guide plate 5 in the third direction z in the backlight module, the adhesive effect of the second portion of the adhesive block is better than the adhesive effect of the first portion of the adhesive block.

[0069] Therefore, if the adhesive block 3 is arranged above the partition gap 12a and the area where the partition gap 12a overlaps the adhesive block 3 is too large, the adhesive effect of the adhesive block 3 is poor.

[0070] In the embodiments of the present application, by making the extension length of the portion of the partition gap 12a covered by the adhesive block 3 as small as possible, that is, as shown in FIG. 4, making the extension length of the portion of the partition gap 12a covered by the adhesive block 3 smaller than the size of the adhesive block 3 in the first direction x and smaller than the size of the adhesive block 3 in the second direction y, or even making the partition gap 12a not overlap the adhesive block 3, that is, as shown in FIG. 2, making the orthogonal projection of the adhesive block 3 on the circuit board 1 located outside the area where the partition gap 12a is located. In this way, the area where the partition gap 12a overlaps the adhesive block 3 can be as small as possible or even not overlap, so that the adhesive block 3 can be arranged above the recessed portion of the first surface at the partition gap 12a as little as possible, thereby improving the adhesive effect of the adhesive block 3.

[0071] Exemplarily, compared with the proportion of the overlapping area of the bonding block 3' and the partition gap 10' in the bonding block 3' shown in FIG. 1, the proportion of the overlapping area of the bonding block 3 and the partition gap 12a in the bonding block 3 in the embodiment of the present application can be reduced by at least 10%.

[0072] In conclusion, the light emitting device provided by the embodiment of the present application comprises a circuit board, a plurality of light emitting units and a plurality of bonding blocks. By letting the orthographic projection of the bonding block on the circuit board be located outside the region where the partition gap between the adjacent first pad and second pad is located, or by letting the extension length of the part of the partition gap between the adjacent first pad and second pad covered by the bonding block be smaller than the size of the bonding block in the first direction and smaller than the size of the bonding block in the second direction, the area of the partition gap overlapping with the bonding block can be ensured to be as small as possible or not to overlap, so as to avoid the bonding block being arranged above the partition gap as much as possible, thereby improving the bonding effect of the bonding block.

[0073] In a possible embodiment, as shown in FIG. 2, the orthographic projection of the first pad 1201 on the plane where the circuit board 1 is located is larger than the area of the orthographic projection of the second pad 1202 on the plane where the circuit board 1 is located. The orthographic projection of the bonding block 3 on the circuit board 1 is located in the region where the first pad 1201 is located.

[0074] In another possible embodiment, as shown in FIG. 4, the orthographic projection of the first pad 1201 on the plane where the circuit board 1 is located is larger than the area of the orthographic projection of the second pad 1202 on the plane where the circuit board 1 is located. The area of the part of the orthographic projection of the bonding block 3 on the circuit board 1 located in the region where the first pad 1201 is located is larger than the area of the part located in the region where the second pad 1202 is located.

[0075] By setting the area of the first pad 1201 to be larger than the area of the second pad 1202, the bonding block 3 can be arranged above the first pad 1201 as much as possible (as shown in FIG. 4), so as to make the area of the partition gap 12a overlapping with the bonding block 3 as small as possible, or the bonding block 3 can be arranged above the first pad 1201 entirely (as shown in FIG. 2), so as to make the partition gap 12a not overlap with the bonding block 3.

[0076] As shown in FIG. 4, the partition gap 12a comprises a first sub-partition gap 121a, a second sub-partition gap 122a and a third sub-partition gap 123a connected in sequence. In the second direction y, the third sub-partition gap 123a is closer to the light emitting unit 2 relative to the first sub-partition gap 121a.

[0077] That is, as shown in FIG. 4, the circuit board 1 has a first side 101 and a second side 102 oppositely arranged, and the light emitting units 2 are distributed on the circuit board 1 at positions close to the first side 101. In the direction in which the second side 102 points to the first side 101, the first sub-partition gap 121a, the second sub-partition gap 122a, and the third sub-partition gap 123a are sequentially connected. Among them, in the first direction x, the third sub-partition gap 123a is located between two adjacent light emitting units 2.

[0078] As shown in FIG. 4, the overall extension direction of the first sub-partition gap 121a and the third sub-partition gap 123a is parallel to the second direction y, and the extension direction of the second sub-partition gap 122a is parallel to the first direction x.

[0079] Since the third sub-partition gap 123a is located between two adjacent light emitting units 2, by arranging the extension direction of the second sub-partition gap 122a to be parallel to the first direction x, the first sub-partition gap 121a is located in the light emitting surface of the light emitting unit 2 in the second direction y, that is, the orthographic projection of the first sub-partition gap 121a in the plane in which the second side 102 is located is located in the orthographic projection of the light emitting unit 2 in the plane in which the second side is located. Since in the first direction x, the plurality of light emitting units 2 and the plurality of bonding blocks 3 are alternately arranged, the partition gap 12a can be avoided as much as possible to overlap the bonding block 3 as much as possible, so that the area of the partition gap 12a and the bonding block 3 is as small as possible or does not overlap.

[0080] Exemplarily, as shown in FIG. 4, in the case where the orthographic projection of the bonding block 3 on the circuit board 1 overlaps the area where the partition gap 12a is located, there is a part of the first sub-partition gap 121a in the partition gap 12a that is covered by the bonding block 3, and there is no part of the second sub-partition gap 122a and the third sub-partition gap 123a in the partition gap 12a that is covered by the bonding block 3.

[0081] In this case, in the second direction y, on the basis of arranging the bonding block 3 between two adjacent light emitting units 2, the bonding block 3 can be extended to the light emitting surface of the light emitting unit 2, so that there is a part covered by the bonding block 3 in the partition gap 12a. In this way, the area of the bonding block 3 can be increased as much as possible while the influence on the light path of the light emitted by the light emitting unit is as small as possible, so that the bonding effect of the bonding block 3 is improved. Since the third sub-partition gap 123a is closer to the light emitting unit 2 than the first sub-partition gap 121a, the width of the third sub-partition gap 123a is generally greater than the width of the first sub-partition gap 121a. Therefore, when there is a part covered by the bonding block 3 in the third sub-partition gap 123a, the bonding effect of the bonding block 3 may be affected due to the excessive overlapping area between the third sub-partition gap 123a and the bonding block 3. Since the extension direction of the second sub-partition gap 122a is parallel to the first direction x, when there is a part covered by the bonding block 3 in the second sub-partition gap 123a, the bonding effect of the bonding block 3 may also be affected due to the excessive overlapping area between the second sub-partition gap 122a and the bonding block 3. Therefore, in the present application, it is necessary to ensure that there is a part covered by the bonding block 3 in the first sub-partition gap 121a in the partition gap 12a. In this way, the bonding area of the bonding block 3 can be ensured to be large, and the probability of affecting the bonding effect of the bonding block 3 by the partition gap 12a can be reduced.

[0082] In a possible embodiment, as shown in FIG. 4, the extension direction of the first sub-partition gap 121a in the partition gap 12a is linear, and the extension direction of the linearly extending first sub-partition gap 121a is parallel to the second direction y.

[0083] In another possible implementation, as shown in FIG. 5, which is a schematic diagram of a planar structure of another light emitting device provided by the present application, the extension direction of the first sub-partition gap 121a is in the shape of a broken line, that is, there is a small bent part in the first sub-partition gap 121a, but the overall extension mode of the first sub-partition gap 121a is still parallel to the second direction y.

[0084] For example, as shown in FIG. 6, which is a partial enlarged view of a first pad and a second pad provided by an embodiment of the present application, the second pad 1202 with a relatively smaller normal projection on the circuit board 1 can include a first conductive part 1202a, a conductive excess part 1202b and a second conductive part 1202c connected in sequence in the second direction y.

[0085] The first conductive portion 1202a has a dimension in the first direction x that is smaller than a dimension of the second conductive portion 1202c in the first direction x. The conductive transition portion 1202b has a dimension in the first direction x that gradually increases in a direction from the first conductive portion 1202a to the second conductive portion 1202c. Here, at least one of the conductive transition portion 1202b and the second conductive portion 1202c is configured to be electrically connected to the conductive circuit 10 in the circuit board 1.

[0086] Since the second pad 1202 has a relatively small area of the orthographic projection on the circuit board 1, the second pad 1202 has a relatively small dimension in the first direction x. In order to facilitate the second pad 1202 to access the conductive circuit 10 in the circuit board 1, the second pad 1202 can be widened locally. For example, the second pad 1202 can be designed to have a conductive transition portion 1202b that gradually increases in the first direction x, so that the conductive transition portion 1202b and the second conductive portion 1202c in the second pad 1202 both have relatively large dimensions in the first direction x. In this way, the conductive transition portion 1202b and / or the second conductive portion 1202c that have relatively large dimensions in the first direction x can be subsequently connected to the conductive circuit 10, so as to ensure that the second pad 1202 can more stably access the conductive circuit 10 in the circuit board 1, and the conductive circuit 10 can more stably provide signals to the second pad 1202.

[0087] In this case, the first sub-blocking gap 121a includes a first sub-gap a1, a connecting sub-gap a2, and a second sub-gap a3 connected in sequence. The first sub-gap a1 is located between the first conductive portion and the first pad 1021, the connecting sub-gap a2 is located between the conductive transition portion and the first pad 1021, and the second sub-gap a3 is located between the second conductive portion and the first pad 1021. The width of the first sub-gap a1 is equal to the width of the connecting sub-gap a2 and the second sub-gap a3. In this case, the first sub-blocking gap 121a has a meandering extension direction.

[0088] It should be noted that, in the case where the first sub-blocking gap 121a has a meandering extension direction, if the first sub-blocking gap 121a has a portion covered by the bonding block 3, the portion of the first sub-blocking gap 121a covered by the bonding block 3 can include a portion of the first sub-gap a1, or a portion of the second sub-gap a3, or a portion of the connecting sub-gap a2. That is, the first sub-gap a1, the connecting sub-gap a2, and the second sub-gap a3 in the first sub-blocking gap 121a can all have portions covered by the bonding block 3. The embodiments of the present application do not limit this.

[0089] It is also to be noted that, in addition to the first conductive portion 1202a, the conductive transition portion 1202b and the second conductive portion 1202c, the second pad 1202 can further include a transition portion 1202d for connecting with the light emitting unit 2. Here, the transition portion 1202d can have a second sub-division gap 122a and a third sub-division gap 123a with the first pad 1201.

[0090] Optionally, as shown in FIG. 7, the plurality of second pads 1202 in the circuit board 1 can be divided into a plurality of pad groups P. Each pad group P can include at least two second pads 1202 arranged continuously in the first direction x, and the two second pads 1202 distributed at the outermost sides in the pad group P are respectively a first second pad P1 and a last second pad P2. It is to be noted that FIG. 7 is only a schematic illustration of the distribution of one pad group P in the circuit board 1.

[0091] Here, in one pad group P, the size of the first conductive portion 1202a in the second direction y in each second pad 1202 gradually decreases along the direction from the first second pad P1 to the last second pad P2, and the size of the second conductive portion 1202c in the second direction y in each second pad P gradually increases along the direction from the first second pad P1 to the last second pad P2.

[0092] Optionally, in one pad group P, the size of the conductive transition portion 1202b in the second direction y in each second pad 1202 is equal.

[0093] That is, for the plurality of first sub-division gaps 121a between the plurality of second pads 1202 in the same pad group P and the plurality of first pads 1201 arranged adjacently, the position of the bend (i.e., the position of the connection sub-gap a2) in the first sub-division gap 121a gradually changes in the second direction y. In this way, it is more conducive to ensure that each second pad 1202 in the same pad group P can be normally connected to the corresponding conductive line 10.

[0094] In the embodiments of the present application, the width of the first sub-division gap 121a is 0.1-0.3 mm, i.e., the size of the first sub-division gap 121a in the first direction x is 0.1-0.3 mm.

[0095] In the prior art, referring to FIG. 1 again, the width of the partition gap 10' is greater than 0.3 mm, i.e. the size of the partition gap 10' in the first direction x' is greater than 0.3 mm. Therefore, compared with the prior art, the embodiments of the present application reduce the area of the partition gap 12a overlapping the adhesive block 3 by making the width of the first sub-partition gap 121a 0.1-0.3 mm, so as to improve the adhesive effect of the adhesive block 3.

[0096] Exemplarily, compared with the related art, when the width of the partition gap 12a in the embodiments of the present application is 0.1 mm, the proportion of the overlapping area of the adhesive block 3 and the partition gap 12a in the adhesive block 3 can be reduced by at least 30%.

[0097] In the embodiments of the present application, the size of the adhesive block 3 in the second direction y is smaller than the minimum distance between the light-emitting unit 2 and the second side 102. Here, the minimum distance between the light-emitting unit 2 and the second side 102 is the distance between the light-emitting surface of the light-emitting unit 2 and the second side 102. By making the adhesive block 3 shorter in the second direction y, the distance between the adhesive block 3 and the second side 102 can be avoided from being too short due to the longer adhesive block 3.

[0098] Exemplarily, the length of the first pad 1201 close to the side edge of the second side 102 is about 2.35 mm, and the length of the second pad 1202 close to the side edge of the second side 102 is about 1.35 mm.

[0099] FIG. 8 is a schematic diagram of the light path of the light emitted by the light-emitting unit according to an embodiment of the present application. As shown in FIG. 8, the light path of the light emitted by the light-emitting unit 2 is not all parallel to the second direction y, but also includes the light path at an angle to the second direction y, i.e. the light emitted by the light-emitting unit 2 includes the light rays obliquely emitted. In an ideal design, in combination with FIG. 3, in the third direction y, the light emitted by the light-emitting unit 2 enters the light guide plate 5 from the side surface of the light guide plate 5, wherein part of the light (first part of the light) meets the total reflection angle of the light guide plate 5, and is emitted from the light-emitting surface of the light guide plate 5 after multiple total reflections in the light guide plate 5; and the other part of the light (second part of the light) does not meet the total reflection angle of the light guide plate 5, and is refracted after being emitted toward the bottom surface (the other surface opposite to the light-emitting surface of the light guide plate 5) of the light guide plate 5, and is emitted toward the circuit board 1. Generally, the surface of the circuit board 1 close to the light guide plate 5 is coated with a reflective layer, so the light rays are subsequently reflected on the surface of the circuit board 1, and enter the light guide plate 5 after being refracted on the bottom surface of the light guide plate 5. In the ideal design, the brightness of the light emitted from different positions of the light guide plate 5 is relatively uniform.

[0100] If the distance between the bonding block 3 and the second side 102 is too close, the second part of the light will be refracted on the bottom surface of the light guide plate 5, pass through the bonding block 3, be reflected on the surface of the circuit board 1 and enter the bonding block 3, and finally be refracted on the bottom surface of the light guide plate 5 and enter the light guide plate 5. Since the transparency of the bonding block 3 is limited, the brightness of the light passing through the bonding block 3 will decrease. Therefore, the problem of uneven brightness of the light emitted by the light guide plate 5 will occur.

[0101] In the embodiment of the present application, the size of the bonding block 3 in the second direction y is less than the minimum distance between the light emitting unit 2 and the second side 102, so that the bonding block 3 is not too long and the distance between the bonding block 3 and the second side 102 is not too close. In this way, the light emitted by the light emitting unit 2 can pass through the bonding block 3 as much as possible, thereby facilitating the light emitted by the light guide plate 5 to be more uniform in brightness.

[0102] For example, as shown in FIG. 8 and FIG. 9, the bonding block 3 includes a first bonding part 31 and a second bonding part 32 connected together, the first bonding part 31 is closer to the first side 101 relative to the second bonding part 32, and the size of the first bonding part 31 in the first direction x is less than the size of the second bonding part 32. Since the first bonding part 31 is closer to the first side 101, the first bonding part 31 is closer to the light emitting unit 2.

[0103] Compared with the bonding block 3' in the related art shown in FIG. 1, the bonding block 3 in the embodiment of the present application has a larger area, so that the bonding effect can be improved. For example, the area of the orthographic projection of the bonding block 3 on the circuit board 1 is more than 1 times the area of the orthographic projection of the bonding block 3' on the circuit board 1' in the related art shown in FIG. 1.

[0104] In addition, by setting the size of the first bonding part 31 in the first direction x to be smaller, the influence of the first bonding part 31 on the light path of the light emitted by the light emitting unit 2 can be reduced as much as possible, and the size of the second bonding part 32 in the first direction x is set to be larger to increase the bonding area of the bonding block 3 and improve the bonding effect of the bonding block 3.

[0105] FIG. 10 is a schematic diagram of a light path of light emitted by a light emitting unit according to another embodiment of the present application. In a possible embodiment, as shown in FIG. 10, the orthographic projections of the first bonding part 31 and the second bonding part 32 on the circuit board 1 are both rectangular, and the size of the first bonding part 31 in the first direction x is less than the size of the second bonding part 32. Alternatively, the orthographic projection of the bonding block 3 on the circuit board 1 can also be rectangular.

[0106] In another possible embodiment, as shown in FIG. 8 and FIG. 9, the shape of the normal projection of the first adhesive portion 31 on the circuit board 1 is rectangular, and the shape of the normal projection of the second adhesive portion 32 on the circuit board 1 is trapezoidal.

[0107] Compared with the embodiment shown in FIG. 10, since the shape of the normal projection of the second adhesive portion 32 on the circuit board 1 is trapezoidal instead of rectangular, the side of the trapezoidal-shaped second adhesive portion 32 shown in FIG. 8 conforms to the light emitted obliquely by the light-emitting unit 2 more, i.e., the area of overlap between the normal projection of the second adhesive portion 32 on the circuit board 1 and the normal projection of the light emitted obliquely by the light-emitting unit 2 on the circuit board 1 is smaller than the area of overlap between the normal projection of the second adhesive portion 32 on the circuit board 1 and the normal projection of the light emitted obliquely by the light-emitting unit 2 on the circuit board 1 in FIG. 10. Therefore, setting the second adhesive portion 32 as trapezoidal helps to improve the problem of uneven brightness of the light emitted by the light guide plate 5 caused by the light emitted by the light-emitting unit 2 passing through the adhesive block 3.

[0108] Optionally, as shown in FIG. 9, the second adhesive portion 32 has two sharp corners distributed in the first direction x, and the tips of the two sharp corners are both arc-shaped. Since the shape of the second adhesive portion 32 is trapezoidal, in the case that the top side of the trapezoid close to the second side 102, the bottom side of the trapezoid close to the first side 101, and the side of the trapezoid remain unchanged, the arc design of the two sharp corners of the second adhesive portion 32 distributed in the first direction x can reduce the area of overlap between the normal projection of the second adhesive portion 32 on the circuit board 1 and the normal projection of the light emitted obliquely by the light-emitting unit 2 on the circuit board 1, thereby helping to improve the problem of uneven brightness of the light emitted by the light guide plate 5 caused by the light emitted by the light-emitting unit 2 passing through the adhesive block 3.

[0109] In the embodiments of the present application, in the case that the normal projection of the adhesive block 3 on the circuit board 1 overlaps with the area where the partition gap 12a is located, the normal projection of the second adhesive portion 32 in the adhesive block 3 on the circuit board 1 overlaps with the area where the partition gap 12a is located, and the normal projection of the first adhesive portion 31 on the circuit board 1 does not overlap with the area where the partition gap 12a is located. That is, the normal projection of the second adhesive portion 32 in the adhesive block 3 on the circuit board 1 can overlap with part of the first sub-partition gap 121a in the partition gap 12a. Here, the shape of the normal projection of the second adhesive portion 32 on the circuit board 1 is trapezoidal, and therefore, only a small part of the second adhesive portion 32 overlaps with part of the first sub-partition gap 121a. For example, only one sharp corner of the second adhesive portion 32 overlaps with the area where the partition gap 12a is located. In this way, the overlapping area of the normal projection of the adhesive block 3 on the circuit board 1 and the area where the partition gap 12a is located can be further reduced.

[0110] It should be noted that in the foregoing embodiments, the extending direction of the partition gap 12a is exemplarily illustrated as a broken line. In other possible embodiments, the overall extending direction of the partition gap 12a can also intersect the second direction y. FIG. 11 is a schematic diagram of a planar structure of another light emitting device according to an embodiment of the present application. As shown in FIG. 11, the extending direction of the partition gap 12a intersects the first direction x and the second direction y.

[0111] In the embodiment shown in FIG. 11, by setting the overall extending direction of the partition gap 12a to intersect the first direction x and the second direction y, part of the partition gap 12a is arranged on the light emitting surface of the light emitting unit 2, and since the adhesive block 3 is arranged as far as possible away from the light emitting surface of the light emitting unit 2, the overlapping area of the adhesive block 3 and the partition gap 12a can be reduced. As shown in FIG. 11, the part of the adhesive block 3 that overlaps the partition gap 12a is only located on the lower right side and the upper left side of the adhesive block 3, and thus the overlapping area is smaller than the overlapping area in the related art shown in FIG. 1. In this way, the adhesion effect of the adhesive block 3 can be improved.

[0112] Exemplarily, as shown in FIG. 11, the angle between the extending direction of the partition gap 12a and the first direction x ranges from 30 degrees to 60 degrees. If the angle between the extending direction of the partition gap 12a and the first direction x is greater than 60 degrees or less than 30 degrees, the overlapping area of the partition gap 12a and the adhesive block 3 will be relatively large, which is not conducive to improving the adhesion effect of the adhesive block 3. Moreover, if the circuit board 1 is a flexible circuit board and the angle between the extending direction of the partition gap 12a and the first direction x is less than 30 degrees, the flexible circuit board will not be easy to bend in the first direction x (the bending axis is parallel to the second direction y).

[0113] FIG. 12 is a schematic diagram of a cross-sectional structure of a circuit board according to an embodiment of the present application. As shown in FIG. 12, the circuit board 1 comprises, in sequence, a second protective layer 17, a second connecting layer 16, a second wiring layer 13, a substrate layer 11, a first wiring layer 12, a first connecting layer 14 and a first protective layer 15. The first wiring layer 12 is located between the substrate layer 11 and the plurality of light emitting units 2, and a plurality of first pads 1201 and a plurality of second pads 1202 are located on the first wiring layer 12. That is, the light emitting units 2 are located on the top surface of the circuit board 1 shown in FIG. 12.

[0114] Exemplarily, the material of the substrate layer can be a flexible material such as polyimide (PI), so that the circuit board 1 is a flexible circuit board.

[0115] Exemplarily, the first wiring layer 12 and the second wiring layer 13 are made of high-conductivity metal materials, so as to transmit electrical signals to the light emitting units 2. The first wiring layer 12 can be provided with the first solder pad 1201 and the second solder pad 1202 for soldering the light emitting units 2, and the second wiring layer 13 can be provided with wirings for connecting the circuit board 1 with external devices and wirings for connecting different light emitting units 2. Exemplarily, the first wiring layer 12 and the second wiring layer 13 respectively include a plurality of hollow regions.

[0116] Exemplarily, the first protective layer 15 and the second protective layer 17 respectively serve to protect the first wiring layer 12 and the second wiring layer 13. The first protective layer 15 and the second protective layer 17 can be made of flexible materials, so as to be bent.

[0117] Exemplarily, the first connecting layer 14 serves to connect the first wiring layer 12 and the first protective layer 15, and part of the first connecting layer 14 is located in the hollow region of the first wiring layer 12. The second connecting layer 16 serves to connect the second wiring layer 13 and the second protective layer 17, and part of the second connecting layer 16 is located in the hollow region of the second wiring layer 13.

[0118] Optionally, the first connecting layer 14 is formed by solidifying a liquid first connecting layer material, and the second connecting layer 16 is formed by solidifying a liquid second connecting layer material.

[0119] Exemplarily, the thickness of the first connecting layer 14 is greater than the thickness of the first wiring layer 12, so as to better serve to connect the first connecting layer 14 and the first protective layer 15. Exemplarily, the thickness of the second connecting layer 16 is greater than the thickness of the second wiring layer 13, so as to better serve to connect the second connecting layer 16 and the second protective layer 17.

[0120] In the embodiment of the present application, as shown in FIG. 12, the sum of the thickness of the substrate layer 11 and the first wiring layer 12 is greater than the sum of the thickness of the first connecting layer 14 and the first protective layer 15, and the sum of the thickness of the substrate layer 11 and the second wiring layer 13 is greater than the sum of the thickness of the second connecting layer 16 and the second protective layer 17. In this way, the total thickness of the substrate layer 11, the first wiring layer 12 and the second wiring layer 13 in the circuit board 1 is relatively large, which is beneficial to improve the stiffness of the circuit board 1, so that the circuit board 1 is less likely to be wrinkled. Therefore, the light emitting device in the embodiment of the present application is particularly suitable for display devices with extremely thin design. If the display device is relatively thin, the circuit board 1 is also relatively thin, and the possibility of being wrinkled is greater. In the embodiment of the present application, the thicknesses of different structural layers are designed, so as to reduce the possibility of the circuit board 1 being wrinkled.

[0121] Exemplarily, the ratio of the sum of the thickness of the substrate layer 11, the first wiring layer 12 and the second wiring layer 13 to the thickness of the circuit board 1 is 30% to 50%.

[0122] As shown in FIG. 12, the circuit board 1 further includes a reflective layer 18 to reflect the light emitted by the light emitting units 2 and passing through the light guide plate to the surface of the circuit board 1. The reflective layer 18 is located on the side of the first protective layer 17 away from the substrate layer 11. The reflective layer 18 can be made of white oil.

[0123] As shown in FIG. 12, the circuit board 1 further includes a reinforcing layer 19. When the total thickness of the circuit board 1 is large, the reinforcing layer 19 can be provided to further improve the stiffness of the circuit board 1. Optionally, the reinforcing layer 19 is made of polyimide (PI).

[0124] Optionally, when the total thickness of the circuit board 1 is greater than 0.15 mm, the reinforcing layer 19 can be provided, for example, the thickness of the substrate layer 11 is 0.12 mm, and the reinforcing layer 19 is 0.08 mm thick.

[0125] Optionally, when the total thickness of the circuit board 1 is small, for example, when the total thickness of the circuit board 1 is less than or equal to 0.15 mm, the reinforcing layer 19 can not be provided.

[0126] The second wiring layer 13 is further described below. FIG. 13 is a schematic diagram of a planar structure of another light emitting device provided by the embodiments of the present application. As shown in FIG. 13, the light emitting device includes a plurality of light emitting units 2, for example, can include N light emitting units 2, N is a positive integer.

[0127] Optionally, N can be 88, and FIG. 13 only schematically shows 7 light emitting units, numbered from left to right as 9, 10, 11, 17, 18, 81, and 82.

[0128] As shown in FIG. 13, in the first direction x, the plurality of light emitting units 2 includes a plurality of light emitting unit groups arranged in sequence, and each light emitting unit group includes M light emitting units 2, M is a positive integer and M is less than N. For example, the plurality of light emitting units can include 11 light emitting unit groups arranged in sequence, and each light emitting unit group includes 8 light emitting units 2, i.e., M is 8.

[0129] As shown in FIG. 13, the second trace layer 13 includes a plurality of traces, and the second trace layer 13 is configured to electrically connect the xth light emitting unit 2 in each light emitting unit group 20, where x is a positive integer and x is less than or equal to M. That is, the first light emitting unit in each light emitting unit group is electrically connected in sequence, for example, the first, ninth, seventeenth, twenty-fifth, thirty-third, forty-first, forty-ninth, fifty-seventh, sixty-fifth, seventy-third and eighty-first light emitting units 2 are electrically connected in sequence to form a first group of electrically connected light emitting units 2; the second, tenth, eighteenth, twenty-sixth, thirty-fourth, forty-second, fiftieth, fifty-eighth, sixty-sixth, seventy-fourth and eighty-second light emitting units 2 are electrically connected in sequence to form a second group of electrically connected light emitting units 2, and so on.

[0130] In this way, the sum of the lengths of the plurality of traces in the second trace layer 13 for electrically connecting the light emitting units 2 in the first group of electrically connected light emitting units 2 is similar to or the same as the sum of the lengths of the plurality of traces in the second trace layer 13 for electrically connecting the light emitting units 2 in the second group of electrically connected light emitting units 2. In this way, the total impedance of the plurality of traces in the second trace layer 13 for electrically connecting the light emitting units 2 in the first group of electrically connected light emitting units 2 is similar to or the same as the total impedance of the plurality of traces in the second trace layer 13 for electrically connecting the light emitting units 2 in the second group of electrically connected light emitting units 2, thereby reducing the brightness difference between different light emitting units 2.

[0131] In the embodiment shown in FIG. 13, it can be seen that the plurality of traces in the second trace layer 13 include a trace connecting the ninth light emitting unit 2 and the seventeenth light emitting unit 2, and a trace connecting the tenth light emitting unit 2 and the eighteenth light emitting unit 2.

[0132] For example, the substrate layer 11 includes a plurality of transfer vias 110 to facilitate electrical connection between the traces in the second trace layer 13 and the first pads 1201 or the second pads 1202 in the first trace layer 12.

[0133] FIG. 14 is a plan view of another light emitting device according to an embodiment of the present application. As shown in FIG. 14, the light emitting device further includes a release film 4, which is located on the side of the plurality of adhesive blocks 3 away from the plurality of first pads 1201 and the plurality of second pads 1202. In the manufacturing process of the light emitting device, the plurality of adhesive blocks 3 can be first arranged on the release film 4, and then the plurality of adhesive blocks 3 can be transferred to the circuit board 1 through the release film 4, and then the release film 4 can be torn off to facilitate the connection between the adhesive blocks 3 and the light guide plate.

[0134] As shown in FIG. 14, the release film 4 includes a main body 41 and a plurality of protruding portions 42 connected to the main body 41, the plurality of protruding portions 42 are located on the side of the main body 41 close to the plurality of light emitting units 2, and in the first direction x, the plurality of light emitting units 2 and the plurality of protruding portions 42 are arranged alternately, and the protruding portion 42 is located between two adjacent light emitting units 2. By arranging the protruding portion 42, in the process of transferring the plurality of adhesive blocks 3 to the circuit board 1 through the release film 4, the protruding portion 42 can play a positioning role to more conveniently and accurately connect the adhesive block 3 with the circuit board 1.

[0135] In summary, the light emitting device provided by the embodiments of the present application includes a circuit board, a plurality of light emitting units and a plurality of adhesive blocks. By arranging the normal projection of the adhesive block on the circuit board to be located outside the region where the partition gap between the adjacent first pad and second pad is located; or arranging the extension length of the part covered by the adhesive block in the partition gap to be less than the size of the adhesive block in the first direction and less than the size of the adhesive block in the second direction. The area of the partition gap overlapping with the adhesive block can be ensured to be as small as possible or not overlapping, so as to avoid the adhesive block being arranged above the partition gap as much as possible, so as to improve the adhesive effect of the adhesive block.

[0136] FIG. 15 is a flow diagram of a manufacturing method of a light emitting device provided by an embodiment of the present application. As shown in FIG. 15, the method includes:

[0137] Step 1301: providing a circuit board. The circuit board includes a plurality of first pads and a plurality of second pads, the plurality of first pads and the plurality of second pads are arranged alternately in the first direction, and the first pad and the second pad arranged adjacently have a partition gap therebetween.

[0138] Step 1302: manufacturing a plurality of light emitting units and a plurality of adhesive blocks on the circuit board.

[0139] The light emitting units are electrically connected with the adjacent first pad and second pad respectively. The plurality of adhesive blocks are arranged on the same side of the plurality of light emitting units in the second direction, and the plurality of adhesive blocks and the plurality of light emitting units are arranged alternately in the first direction, and the second direction intersects with the first direction. The normal projection of the adhesive block on the circuit board is located outside the region where the partition gap is located; or the extension length of the part covered by the adhesive block in the partition gap is less than the size of the adhesive block in the first direction and less than the size of the adhesive block in the second direction.

[0140] In summary, the manufacturing method of the light emitting device provided by the embodiments of the present application is used to manufacture a light emitting device including a circuit board, a plurality of light emitting units and a plurality of adhesive blocks. The adhesive blocks are arranged such that the orthographic projection of the adhesive blocks on the circuit board is located outside the region where the partition gap between the adjacent first pad and the second pad is located, or the extension length of the portion of the partition gap between the adjacent first pad and the second pad covered by the adhesive blocks is smaller than the size of the adhesive blocks in the first direction and smaller than the size of the adhesive blocks in the second direction. The area of the partition gap overlapping with the adhesive blocks can be ensured to be as small as possible or not overlapping, so that the adhesive blocks are avoided to be arranged above the partition gap as much as possible, and the adhesive effect of the adhesive blocks is improved.

[0141] FIG. 16 is a schematic view of a cross-sectional structure of a backlight module provided by the embodiments of the present application, and FIG. 17 is a schematic view of a planar structure of a backlight module provided by the embodiments of the present application. As shown in FIG. 16 and FIG. 17, the backlight module includes a light guide plate 5 and any of the light emitting devices described above, the light emitting surface of the light emitting device faces the side surface of the light guide plate, and the circuit board in the light emitting device is adhered to the back surface of the light guide plate 5 by the adhesive blocks. Here, the back surface of the light guide plate 5 refers to the surface opposite to the light emitting surface of the light guide plate 5. In addition, the backlight module does not include the release film 4 described above. Here, the light emitting surface of the light emitting device faces the side surface of the light guide plate 5, that is, the light emitting surface of the plurality of light emitting units 2 faces the side surface of the light guide plate 5.

[0142] The backlight module has the same effects as the light emitting device described above, and will not be described herein again.

[0143] The embodiments of the present application further provide a display device, which includes the backlight module described above and a liquid crystal display panel located on the light emitting side of the backlight module. The backlight module is used to provide a light source for the liquid crystal display panel. Here, the light emitting side of the backlight module refers to the light emitting surface of the light guide plate 5.

[0144] For example, the display device provided by the embodiments of the present application can be a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator or any product or component having a display function.

[0145] The display device has the same effects as the display panel described above, and will not be described herein again.

[0146] The display device usually needs to undergo reliability test before leaving factory. The test conditions of the reliability test include high temperature, high humidity, high-low temperature cycle and the like. Therefore, the light guide plate 5 may expand and then shrink, or repeatedly expand and shrink during the reliability test. In the display device, the display device further comprises a printed circuit board (PCB), the surface of the aforementioned circuit board 1 away from the light emitting unit is connected with the printed circuit board and the connection is relatively firm; and the light emitting surface of the light guide plate 5 is connected with the liquid crystal display panel and the connection is relatively firm.

[0147] Therefore, if the bonding effect of the bonding block 3 is poor, after the reliability test, in combination with FIGS. 16 and 17, the expansion and shrinkage of the light guide plate 5 may cause the position of the bonding block 3 to deviate in the first direction x, so that too much part of the bonding block 3 enters the light emitting surface of the light emitting unit 2, causing the light emitting brightness of the backlight module to be uneven, affecting the display effect.

[0148] In addition, since the light emitting surface of the light guide plate 5 is connected with the liquid crystal display panel and the connection is relatively firm, during the reliability test, it can be considered that the position of the light emitting surface of the light guide plate 5 changes little or does not change, while the position of the bottom surface of the light guide plate 5 may deviate to the side away from the light emitting device along the third direction z, and the position of the side surface of the light guide plate 5 may deviate to the side away from the light emitting device along the second direction y, so that the light emitted by the light emitting unit 2 cannot all enter the light guide plate 5 through the side surface of the light guide plate 5 after the reliability test. Therefore, the same size of current is input to the light emitting device before and after the reliability test, and the brightness of the backlight module after the reliability test is reduced, causing the brightness of the display device to be lower than the set brightness, that is, after the reliability test, a larger current needs to be input to the light emitting device to make the display device reach the set brightness, which will cause the power consumption to rise.

[0149] For example, in the related art, the brightness of the display device after the reliability test is reduced by about 5% compared with the display device before the reliability test; while in the embodiment of the present application, the brightness of the display device after the reliability test is reduced by only about 3% compared with the display device before the reliability test.

[0150] Therefore, the bonding effect of the bonding block 3 in the embodiment of the present application is good, which can improve the aforementioned problem of uneven brightness of the backlight module and is beneficial to reduce power consumption.

[0151] Meanwhile, the display device provided by the embodiment of the present application is also applicable to a display device with narrow frame design. In the plane parallel to the first direction x and parallel to the second direction y, the distance between the light emitting unit 2 and the display area of the display device is A, and the distance between two adjacent light emitting units 2 in the first direction x is P. The A / P value is determined by the optical design of the light guide plate, and thus the A / P value is usually fixed. Therefore, compared with the display device without narrow frame design, in the display device with narrow frame design, the A value is reduced, and the corresponding P value also needs to be reduced, and thus the bonding area between the bonding block 3 and the circuit board 1 is also reduced, and thus it is more necessary to reduce the proportion of the overlapping area between the bonding block 3 and the partition gap 12a in the bonding block 3.

[0152] Therefore, the light emitting device provided by the embodiment of the present application is particularly suitable for a display device with low power consumption requirement and a display device with narrow frame design.

[0153] It should be noted that the terms used in the embodiment part of the present application are only used for explaining the embodiments of the present application, and are not intended to limit the present application. Unless otherwise defined, the technical terms or scientific terms used in the embodiment of the present application should be understood as the usual meaning understood by those skilled in the art to which the present application belongs. The terms "first", "second" and similar terms used in the specification and claims of the patent application of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. Similarly, "one" or "a" and similar terms do not represent a quantity limitation, but represent the existence of at least one. The terms "including", "containing" and similar terms mean that the elements or objects appearing before "including" or "containing" cover the elements or objects listed after "including" or "containing" and their equivalents, and do not exclude other elements or objects. The orientation terms mentioned in the present application, such as "top", "bottom", "upper", "lower", "left" or "right", are only the direction of the drawing, and thus the orientation terms are used to better and more clearly illustrate and understand the present application, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus cannot be understood as a limitation on the present application.

[0154] The above is only an optional embodiment of the present application, and does not limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A light emitting device, characterized by, The light emitting device comprises a circuit board (1), a plurality of light emitting units (2) and a plurality of adhesive blocks (3); The circuit board comprises a plurality of first pads (1201) and a plurality of second pads (1202), the plurality of first pads (1201) and the plurality of second pads (1202) are arranged alternately in a first direction, and the first pad (1201) and the second pad (1202) adjacent to each other have a partition gap (12a) therebetween; The plurality of light emitting units (2) are located on the circuit board (1), and the light emitting unit (2) is electrically connected with the first pad (1201) and the second pad (1202) adjacent thereto, respectively; The plurality of adhesive blocks (3) are located on the circuit board (1), and the plurality of adhesive blocks (3) are arranged on the same side of the plurality of light emitting units (2) in a second direction, and the second direction intersects the first direction; The normal projection of the adhesive block (3) on the circuit board (1) is located outside the area where the partition gap (12a) is located; or the extension length of the part of the partition gap (12a) covered by the adhesive block (3) is less than the size of the adhesive block (3) in the first direction and less than the size of the adhesive block (3) in the second direction.

2. The light emitting device of claim 1, wherein The normal projection of the first pad (1201) on the plane of the circuit board (1) is greater than the area of the normal projection of the second pad (1202) on the plane of the circuit board (1); The normal projection of the adhesive block (3) on the circuit board (1) is located in the area where the first pad (1201) is located; or the area of the part of the normal projection of the adhesive block (3) on the circuit board (1) located in the area where the first pad (1201) is located is greater than the area of the part located in the area where the second pad (1202) is located.

3. The light emitting device of claim 2, wherein The partition gap (12a) comprises a first sub-partition gap (121a), a second sub-partition gap (122a) and a third sub-partition gap (123a) connected in sequence; The overall extension direction of the first sub-partition gap (121a) and the third sub-partition gap (123a) is parallel to the second direction, and the extension direction of the second sub-partition gap (122a) is parallel to the first direction In the second direction, the third sub-partition gap (123a) is closer to the light emitting unit (2) relative to the first sub-partition gap (121a). In the case that the normal projection of the adhesive block (3) on the circuit board (1) overlaps with the area where the partition gap (12a) is located, there is a part covered by the adhesive block (3) in the first sub-partition gap (121a), and there is no part covered by the adhesive block (3) in the second sub-partition gap (122a) and the third sub-partition gap (123a).

4. The light emitting device of claim 3, wherein The width of the first sub-partition gap (121a) is 0.1-0.3mm.

5. The light emitting device of claim 4, wherein ​ 6. The light emitting device of claim 3, wherein The second pad (1202) comprises a first conductive part (1202a), a conductive transition part (1202b) and a second conductive part (1202c) connected in sequence in the second direction; The size of the first conductive part (1202a) in the first direction is smaller than the size of the second conductive part (1202c) in the first direction; and the size of the conductive transition part (1202b) in the first direction gradually increases from the first conductive part (1202a) to the second conductive part (1202c). At least one of the conductive transition part (1202b) and the second conductive part (1202c) is used to electrically connect with a conductive circuit (10) in the circuit board (1).

7. The light emitting device of claim 6, wherein The first sub-partition gap (121a) comprises a first sub-gap (a1), a connecting sub-gap (a2) and a second sub-gap (a3) connected in sequence; The first sub-gap (a1) is located between the first conductive part (1202a) and the first pad (1021), the connecting sub-gap (a2) is located between the conductive transition part (1202b) and the first pad (1021), and the second sub-gap (a3) is located between the second conductive part (1202c) and the first pad (1021); The width of the first sub-gap (a1) is equal to the width of the connecting gap (a2), and equal to the width of the second sub-gap (a3).

8. The light emitting device of claim 6, wherein The plurality of second pads (1202) are divided into a plurality of pad groups (P), one pad group (P) comprising at least two second pads (1202) arranged continuously in the first direction x, and the two second pads (1202) distributed at the outermost sides in one pad group (P) are respectively a first second pad (P1) and a last second pad (P2); In one pad group (P), the size of the first conductive part (1202a) in the second direction of each second pad (1202) gradually decreases from the first second pad (P1) to the last second pad (P2), and the size of the second conductive part (1202c) in the second direction of each second pad (1202) gradually increases from the first second pad (P1) to the last second pad (P2).

9. The light emitting device of claim 6, wherein In one pad group (P), the size of the conductive transition part (1202b) in the second direction of each second pad (1202) is equal.

10. The light emitting device of claim 1, wherein The extension direction of the partition gap (12a) intersects the first direction and the second direction; The angle between the extension direction of the partition gap (12a) and the first direction ranges from 30 degrees to 60 degrees.

11. The light emitting device according to any one of claims 1 to 10, wherein The circuit board has a first side (101) and a second side (102) arranged oppositely, and the light-emitting units (2) are distributed on the circuit board (1) at positions close to the first side (101). In the second direction, the size of the adhesive block (3) is smaller than the minimum distance between the light emitting unit (2) and the second side (102).

12. The light emitting device of claim 11, wherein, The adhesive block (3) comprises a first adhesive part (31) and a second adhesive part (32) connected together, the first adhesive part (31) is closer to the first side (101) than the second adhesive part (32), and in the first direction, the size of the first adhesive part (101) is smaller than the size of the second adhesive part (102).

13. The light emitting device of claim 12, wherein In the case that the orthogonal projection of the adhesive block (3) on the circuit board (1) overlaps with the area where the partition gap (12a) is located, the orthogonal projection of the second adhesive part (32) on the circuit board (1) overlaps with the area where the partition gap (12a) is located, and the orthogonal projection of the first adhesive part (31) on the circuit board (1) does not coincide with the area where the partition gap (12a) is located.

14. The light emitting device of claim 12, wherein The orthogonal projection of the first adhesive part (31) on the circuit board (1) is rectangular, and the orthogonal projection of the second adhesive part (32) on the circuit board (1) is trapezoidal.

15. The light emitting device of claim 14, wherein, The second adhesive part (32) has two sharp corners distributed in the first direction, and the tips of the two sharp corners are arc-shaped.

16. The light emitting device of claim 15, wherein In the case that the orthogonal projection of the adhesive block (3) on the circuit board (1) overlaps with the area where the partition gap (12a) is located, the orthogonal projection of one of the sharp corners in the second adhesive part (32) on the circuit board (1) overlaps with the area where the partition gap (12a) is located.

17. The light emitting device according to any one of claims 1 to 10 and 12 to 16, wherein, The circuit board (1) comprises a second protective layer (17), a second connection layer (16), a second trace layer (13), a substrate layer (11), a first trace layer (12), a first connection layer (14) and a first protective layer (15) which are sequentially laminated; The first trace layer (12) is located between the substrate layer (11) and the plurality of light emitting units (2), and the plurality of first pads (1201) and the plurality of second pads (1202) are located in the first trace layer (12); The sum of the thicknesses of the substrate layer (11) and the first trace layer (12) is greater than the sum of the thicknesses of the first connection layer (14) and the first protective layer (15); The sum of the thicknesses of the substrate layer (11) and the second trace layer (13) is greater than the sum of the thicknesses of the second connection layer (16) and the first protective layer (17). The light emitting device further comprises a release film (4) located on the side of the plurality of adhesive blocks (3) away from the plurality of first pads (1201) and the plurality of second pads (1202).

18. The light emitting device according to any one of claims 1 to 10 and 12 to 16, wherein, ​ The release film (4) comprises a main body (41) and a plurality of protruding portions (42) connected to the main body (41), the plurality of protruding portions (42) are located on a side of the main body (41) close to the plurality of light emitting units (2), and in the first direction, the plurality of light emitting units (2) and the plurality of protruding portions (42) are arranged alternately, and the protruding portion (42) is located between two adjacent light emitting units (2).

19. A backlight module, characterized in that, The backlight module comprises a light guide plate (5) and the light emitting device according to any one of claims 1 to 18, the light emitting surface of the light emitting device faces the side surface of the light guide plate (5), and the circuit board in the light emitting device is bonded to the back surface of the light guide plate (5) through a plurality of bonding blocks.

20. A liquid crystal display device, characterized by comprising: The display device comprises the backlight module according to claim 19, and a liquid crystal display panel located on the light emitting side of the backlight module.

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